# /usr/bin/env python

import sys

print('Hello world!')

print(abs(4))
print(abs(-4))

# 2.1
myString = "Hello world"
print(myString)

print("%s is number %d!" % ("php", 1))

print(1, 2, 3, file=sys.stdout)

# 2.2
username = input('Enter your username: ')
print('Your username is %s' % username)
num = input('Enter a numer ?')
print('Double your number: %d' % (int(num) * 2))


# 2.3
# one comment
def foo():
    "This is a doc string."
    return True


help(foo)
